Real Madrid legend Mesut Ozil laid into FC Barcelona ahead of a El Clasico by advising the Catalans to stop complaining about referees during an interview with MARCA.
After impressing at the 2010 World Cup with Germany, Ozil joined Los Blancos from Werder Bremen following the tournament and won every Spanish trophy on offer including La Liga under Jose Mourinho.
Madrid and Ozil's haul together could have perhaps been bigger, though, as he confessed to MARCA on the eve of a league-deciding Clasico at the Bernabeu on Sunday.
"At that time it was the most important match in the world of football," he said when asked to reminisce about his appearances in the world's biggest derby.
"Unfortunately for us, Barca was perhaps the best Barca in history. Pep's [Guardiola] Barca was on another level, certainly different from the current Barca. I think right now at a global level the focus is more on games like Liverpool-Manchester City or other Premier League duels."
"I think the Clasico has gone down [in level] and it's a shame. But that's not Real Madrid's fault, as they are undoubtedly one of the best teams in the world. The problem is Barca, who have lost potential."
Ozil called clashes between Mourinho and Guardiola, which also involved Lionel Messi and Cristiano Ronaldo facing off "the pinnacle of football".
"Many fans still miss that era," he pointed out.
Asked to give his thoughts on the match between the two European giants this weekend, Ozil "definitely" sees league leaders Real Madrid as favourites.
"Barcelona are fighting, they're trying. They have good players in all positions, but they've had too many injuries this season and maybe they should look a little bit more at themselves and their mistakes and not always complain about the referees," Ozil suggested.
"This doesn't help. Madrid are having a fantastic season. I didn't expect it after Karim [ Benzema] left the club, but they're doing very well."
Benzema's absence hasn't been felt as badly as it could have been because of the goalscoring emergence of Jude Bellingham.
On the Englishman, Ozil said that his first half of the season "was incredible and left everyone speechless".
"The last few weeks he looked a bit tired, but if he wins La Liga, the Champions League and the European Championship he could be a candidate for the Ballon d'Or. He's still very young, it's unbelievable," Ozil added.